AD/BELL 407/6 - Engine to Transmission Driveshaft Replacement

Overview

The Civil Aviation Regulations 1998, under the Civil Aviation Act 1988, was enacted to ensure the safety and efficiency of civil aviation within Australia. Part 39, specifically Section 105, which includes the Schedule of Airworthiness Directives, addresses issues related to the airworthiness of aircraft, including the issuance of directives that aim to correct safety deficiencies. The Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters AD/BELL 407/6 directive, issued on 20 May 1999, mandates the replacement of the engine to transmission driveshaft for specific serial numbers to address a safety issue identified with the current configuration of the driveshaft, which did not meet certification criteria. This directive requires compliance within 50 hours of flight time post its effective date and references a Transport Canada Airworthiness Directive to align with international safety standards. The enactment of this legislation by the Commonwealth of Australia through the Civil Aviation Safety Authority (CASA) aims to ensure that all aircraft operating within Australian airspace meet the highest safety standards. The policy objective behind the Airworthiness Directive is to mitigate potential safety risks by requiring the replacement of the identified non-compliant component, thereby maintaining the airworthiness of the affected Bell (BHTC) Model 407 helicopters and ensuring the safety of all passengers and crew. The directive also mandates that all removed driveshafts be rendered unusable or identified as unairworthy to prevent any further use in aviation.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates Airworthiness Directives for ensuring the safety of civil aviation in Australia. This particular directive, AD/BELL 407/6, applies exclusively to Bell (BHTC) Model 407 helicopters with serial numbers ranging from 53000 to 53002 and 53002 through 53066. The directive requires the replacement of the engine to transmission driveshaft part number 206-340-300-103 with part number 206-340-300-105, in compliance with BHTC Alerts Service Bulletin (ASB) 407-98-19 dated 19 June 1998. The removed driveshafts must be rendered unusable or identified as unairworthy and quarantined from airworthy parts. This directive is enforced under the Civil Aviation Safety Authority and becomes effective from 20 May 1999, requiring compliance within the next 50 hours of flight time post-directive issuance. The directive references Transport Canada Airworthiness Directive CF-98-25R1, indicating a coordinated international approach to airworthiness standards.

Key Provisions

The Civil Aviation Regulations 1998, Part 39 - 105, under the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, specifies the requirements for replacing the engine to transmission driveshaft on Bell Helicopter Textron Canada (BHTC) 407 Series helicopters with certain serial numbers (AD/BELL 407/6). Specifically, section 5/99 mandates the replacement of the driveshaft part number 206-340-300-103 with part number 206-340-300-105. This must be carried out in accordance with the instructions provided in BHTC Alerts Service Bulletin (ASB) 407-98-19 dated 19 June 1998. Furthermore, any removed driveshafts must be rendered unusable or identified as unairworthy and quarantined to prevent their use in other aircraft. These requirements impose several obligations on the owners and operators of the affected Bell helicopters. They must ensure that the specified driveshaft replacement is completed within the next 50 hours of flight time following the effective date of this Airworthiness Directive. This date is set as 20 May 1999. The owners and operators must also ensure that the replacement process adheres strictly to the guidance in the BHTC Alerts Service Bulletin. Additionally, they must ensure that all removed driveshafts are appropriately marked as unairworthy and are securely quarantined to prevent any potential misuse. Failure to comply with these provisions can lead to serious consequences. The Civil Aviation Safety Authority may take enforcement actions against non-compliant operators. Under the Civil Aviation Act 1988, there can be significant penalties for not adhering to Airworthiness Directives. These penalties may include fines and, in severe cases, prosecution under the criminal law. The exact penalties can vary depending on the nature and severity of the breach but can be substantial, reflecting the critical nature of ensuring airworthiness in aviation operations.